Recent scientific advances in early literacy assessment have provided schools with access to critical information about students' foundational beginning reading skills. In this article, we describe how assessment of early literacy skills can help school psychologists promote beginning reading success for all children. First, we identify key skills in early literacy and describe a comprehensive assessment system, "Dynamic Indicators of Basic Early Literacy Skills" (DIBELS), developed to assess essential beginning reading skills. Next, we present a conceptual framework for thinking about early literacy assessment across four distinct purposes: (a) screening, (b) diagnosis, (c) progress monitoring, and (d) student outcomes. Finally, we provide school-based examples that illustrate how DIBELS can be used to assess students' early literacy skills across each of these four purposes and facilitate informed and ongoing instructional decision making. (Contains 1 table, 4 figures and 2 footnotes.)